For muffler: what kind of volume do you want? I run a walker Quietflow on my 40 and am pleased with it. Very “stock” sounding and quiet.
For tires, have you heard of the Deestone? They look similar to what you linked. I have no experience with...
Short notice but some of us 40 guys are planning a meetup on Thursday, 7/31 at 6 pm at Whistle Punk Brewing in Millwood, 9013 E Frederick Ave Spokane.
No agenda or anything, just meeting some other local cruiser folk and talking about whatever...